Effects of the percentage of terminal flowering on postharvest fruit quality in mango (Mangifera indica) 'Calypso'™

The objective of this study was to investigate the relationship between the percentage of flowering terminals, crop load and postharvest fruit quality in the mango cultivar 'Calypso'™ (B74) grown at Dimbulah in North Queensland. The percentage of flowering terminals was manipulated experimentally by removing flowers at anthesis to give eight treatments in which trees had 5, 10, 20, 30, 40, 60, 70 or 80% of their terminals with flowers. Fruit were sampled at harvest, ripened at 23°C and, at eating ripe, were assessed for fruit number and yields per tree and fruit quality parameters including: fruit size (length, width and depth), fruit weight, background skin colour, blush colour, flesh colour, total soluble solids (TSS), dry matter and internal physiological disorders (jelly-seed, soft nose). The 5% crop load treatment (removing 95% of inflorescences from terminals) significantly reduced the average fruit yield per tree. Average fruit weights were highest in trees with 5 and 10% of terminals flowering, followed by trees with 20% of terminals flowering. There was no difference in average fruit weight between trees with 30, 40, 60, 70 or 80% of terminals flowering. Average fruit length increased significantly in trees with 5, 10 and 20% of terminals flowering compared with those with larger numbers of flowering terminals, with the longest in the 5% treatment. Fruit length was similar in treatments with 30% or more terminals flowering. Similar trends were observed for fruit width, with the widest (89.35 mm) and deepest (80.53 mm) fruit found in the 5% treatment. Although the comparative results between treatments confirmed that the highest values of fruit TSS, dry matter and percentage of blush colour occurred in fruit from trees with only 5% of terminals flowering, observations did not differ significantly among treatments.